For instance, cactophilic flies species from the Sonoran desert exhibit various dispersal strategies due their strict host specialization and the different spatial distribution of their host species [66].
Under this evolutionary model the plasticity of plasmids can be explained in relation to life history and overall fitness costs associated with plasmids: those lineages with strict host specialization, particularly lineages undergoing extreme gene loss and accelerated rates of nucleotide evolution (i.e., TG rickettsiae), would no longer need to harbor plasmids.
which display strict host specialization.
which display strict host specialization [ 11, 12].
The seasonal character of these host species would confer a selective advantage to generalist parasites and counterselect strict host specialization.
These results and the smaller genome size of SFBs suggest that during its strict niche specialization, genome reduction has taken place and many metabolic functions have been lost (see below).
The trend has been away from support for strict gender specialization (Cherlin and Walters 1981; Lee, Tufis, and Alwin 2010; Mason and Lu 1988; Pampel 2011; Scott, Alwin, and Braun 1996), but some countries are more conservative than others (Baxter and Kane 1995; Treas and Widmer 2000).
This absence of strict ecological specialization confers a selective advantage because the parasitoids are adapted to B. fusca, which can be locally and temporally dominant (Ong'Amo et al. 2006; Dupas et al. 2008; Calatayud et al. 2014), but can shift to other hosts when or where B. fusca becomes rare.
Hence, the smaller the FS values, the more directly type A species are linked with type B species in the pollinator network, and the less strict is the functional specialization.
The digestive tract exhibits specializations to a strict vegetarian diet.
